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<h2><span class="refentrytitle">Class template exponential_distribution</span></h2>
<p>boost::random::exponential_distribution</p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../boost_random/reference.html#doxygen.headers.exponential__distribution_8hpp" title="Header &lt;boost/random/exponential_distribution.hpp&gt;">boost/random/exponential_distribution.hpp</a>&gt;

</span><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> RealType <span class="special">=</span> <span class="keyword">double</span><span class="special">&gt;</span> 
<span class="keyword">class</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <span class="identifier">RealType</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a2dfb9a99d8bf46c003c64c157eb74984"></a><span class="identifier">input_type</span><span class="special">;</span> 
  <span class="keyword">typedef</span> <span class="identifier">RealType</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a3788a7c0d4451a60a64211c82ab6131f"></a><span class="identifier">result_type</span><span class="special">;</span>

  <span class="comment">// member classes/structs/unions</span>

  <span class="keyword">class</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">{</span>
  <span class="keyword">public</span><span class="special">:</span>
    <span class="comment">// types</span>
    <span class="keyword">typedef</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1abc2ef0d2f481186b85468467b2b9e985"><span class="identifier">distribution_type</span></a><span class="special">;</span>

    <span class="comment">// <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#id-1_3_32_5_6_11_1_1_1_3_2-bb">public member functions</a></span>
    <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1a5a7a73b900d78b2bbd8314e5b053922f"><span class="identifier">param_type</span></a><span class="special">(</span><span class="identifier">RealType</span> <span class="special">=</span> <span class="number">1</span><span class="special">.</span><span class="number">0</span><span class="special">)</span><span class="special">;</span>
    <span class="identifier">RealType</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1a472c6e34127f1d707fbaa2591462ca6b"><span class="identifier">lambda</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>

    <span class="comment">// <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#id-1_3_32_5_6_11_1_1_1_3_3-bb">friend functions</a></span>
    <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
      <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
      <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1a36d2820c7e758fa1a94fdd5d74949e54"><span class="keyword">operator</span><span class="special">&lt;&lt;</span></a><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
    <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
      <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
      <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1aa94ff75dd5871ee80a6fc0a095c75bd0"><span class="keyword">operator</span><span class="special">&gt;&gt;</span></a><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
    <span class="keyword">bool</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1ae6f3b58e629ce7a54b5e18a4f05dbc5a"><span class="keyword">operator</span><span class="special">==</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
    <span class="keyword">bool</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1_1param__type_1aa559d0d98e88e84417364a89b83cf5b2"><span class="keyword">operator</span><span class="special">!=</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="special">}</span><span class="special">;</span>

  <span class="comment">// <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#id-1_3_32_5_6_11_1_1_1_6-bb">public member functions</a></span>
  <span class="keyword">explicit</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a1e9e3846a7d446cd6c91b05e18aa686e"><span class="identifier">exponential_distribution</span></a><span class="special">(</span><span class="identifier">RealType</span> <span class="special">=</span> <span class="number">1</span><span class="special">.</span><span class="number">0</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">explicit</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ad1eeecc9cdc6d2f6190e612bc801dbc9"><span class="identifier">exponential_distribution</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="identifier">RealType</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a78ac00cedda11cb4ee9a15fa30e09354"><span class="identifier">lambda</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">RealType</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ac350e2f35203191c2c22ca46e03f30c0"><span class="identifier">min</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="identifier">RealType</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a6280abb1497f096584c64e4ba386dc57"><span class="identifier">max</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ac62a38b5060faa12ad9a1bac59ab709e"><span class="identifier">param</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="keyword">void</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a62c7b4f26c1a214271bdcdca10def271"><span class="identifier">param</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">void</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a4f0766a5f2504910c34f471de522a8b9"><span class="identifier">reset</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Engine<span class="special">&gt;</span> <span class="identifier">result_type</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a994c38e887adf3eeec16593dcd62582b"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="identifier">Engine</span> <span class="special">&amp;</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Engine<span class="special">&gt;</span> 
    <span class="identifier">result_type</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a0e061e856c2080f5fa8bd92047b62248"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="identifier">Engine</span> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span>

  <span class="comment">// <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#id-1_3_32_5_6_11_1_1_1_7-bb">friend functions</a></span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
    <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a02ab6d24181f1dd6b2f1a387ebe88f95"><span class="keyword">operator</span><span class="special">&lt;&lt;</span></a><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span><span class="special">,</span> 
               <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
    <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
    <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ab44586654c6af4614b03a93f032c3418"><span class="keyword">operator</span><span class="special">&gt;&gt;</span></a><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span><span class="special">,</span> 
               <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">bool</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ab81a315939fe0cddc4f3764d0938406f"><span class="keyword">operator</span><span class="special">==</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">,</span> 
                  <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">bool</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html#doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a442190cef7645076788fef24b574b494"><span class="keyword">operator</span><span class="special">!=</span></a><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">,</span> 
                  <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.32.5.6.10.3.4"></a><h2>Description</h2>
<p>The exponential distribution is a model of  <a class="link" href="../../boost_random/reference.html#boost_random.reference.concepts.random_distribution" title="Random Distribution">random distribution</a>  with a single parameter lambda.</p>
<p>It has <span class="inlinemediaobject"><img src="../../images/random//form_10.png"></span></p>
<p>The implementation uses the "ziggurat" algorithm, as described in</p>
<p> </p>
<div class="blockquote"><blockquote class="blockquote"><p>  "The Ziggurat Method for Generating Random Variables", George Marsaglia and Wai Wan Tsang, Journal of Statistical Software Volume 5, Number 8 (2000), 1-7.  </p></blockquote></div>
<p>  </p>
<div class="refsect2">
<a name="id-1.3.32.5.6.10.3.4.6"></a><h3>
<a name="id-1_3_32_5_6_11_1_1_1_6-bb"></a><code class="computeroutput">exponential_distribution</code> public member functions</h3>
<div class="orderedlist"><ol class="orderedlist" type="1">
<li class="listitem">
<pre class="literallayout"><span class="keyword">explicit</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a1e9e3846a7d446cd6c91b05e18aa686e"></a><span class="identifier">exponential_distribution</span><span class="special">(</span><span class="identifier">RealType</span> lambda <span class="special">=</span> <span class="number">1</span><span class="special">.</span><span class="number">0</span><span class="special">)</span><span class="special">;</span></pre>
<p>Constructs an <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> with a given lambda.</p>
<p>Requires: lambda &gt; 0 </p>
</li>
<li class="listitem">
<pre class="literallayout"><span class="keyword">explicit</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ad1eeecc9cdc6d2f6190e612bc801dbc9"></a><span class="identifier">exponential_distribution</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span> param<span class="special">)</span><span class="special">;</span></pre>
<p>Constructs an <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> from its parameters </p>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">RealType</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a78ac00cedda11cb4ee9a15fa30e09354"></a><span class="identifier">lambda</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns the lambda parameter of the distribution. </p>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">RealType</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ac350e2f35203191c2c22ca46e03f30c0"></a><span class="identifier">min</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns the smallest value that the distribution can produce. </p>
</li>
<li class="listitem">
<pre class="literallayout"><span class="identifier">RealType</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a6280abb1497f096584c64e4ba386dc57"></a><span class="identifier">max</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns the largest value that the distribution can produce. </p>
</li>
<li class="listitem">
<pre class="literallayout"><a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ac62a38b5060faa12ad9a1bac59ab709e"></a><span class="identifier">param</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns the parameters of the distribution. </p>
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<pre class="literallayout"><span class="keyword">void</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a62c7b4f26c1a214271bdcdca10def271"></a><span class="identifier">param</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span> param<span class="special">)</span><span class="special">;</span></pre>
<p>Sets the parameters of the distribution. </p>
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<pre class="literallayout"><span class="keyword">void</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a4f0766a5f2504910c34f471de522a8b9"></a><span class="identifier">reset</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Effects: Subsequent uses of the distribution do not depend on values produced by any engine prior to invoking reset. </p>
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<pre class="literallayout"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Engine<span class="special">&gt;</span> <span class="identifier">result_type</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a994c38e887adf3eeec16593dcd62582b"></a><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span><span class="special">(</span><span class="identifier">Engine</span> <span class="special">&amp;</span> eng<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns a random variate distributed according to the exponential distribution. </p>
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<pre class="literallayout"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> Engine<span class="special">&gt;</span> 
  <span class="identifier">result_type</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a0e061e856c2080f5fa8bd92047b62248"></a><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span><span class="special">(</span><span class="identifier">Engine</span> <span class="special">&amp;</span> eng<span class="special">,</span> <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution_1_1param__type.html" title="Class param_type">param_type</a> <span class="special">&amp;</span> param<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>
<p>Returns a random variate distributed according to the exponential distribution with parameters specified by param. </p>
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<div class="refsect2">
<a name="id-1.3.32.5.6.10.3.4.7"></a><h3>
<a name="id-1_3_32_5_6_11_1_1_1_7-bb"></a><code class="computeroutput">exponential_distribution</code> friend functions</h3>
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<pre class="literallayout"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
  <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
  <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a02ab6d24181f1dd6b2f1a387ebe88f95"></a><span class="keyword">operator</span><span class="special">&lt;&lt;</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_ostream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> os<span class="special">,</span> 
             <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> ed<span class="special">)</span><span class="special">;</span></pre>
<p>Writes the distribution to a std::ostream. </p>
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<pre class="literallayout"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> CharT<span class="special">,</span> <span class="keyword">typename</span> Traits<span class="special">&gt;</span> 
  <span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> 
  <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ab44586654c6af4614b03a93f032c3418"></a><span class="keyword">operator</span><span class="special">&gt;&gt;</span><span class="special">(</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">basic_istream</span><span class="special">&lt;</span> <span class="identifier">CharT</span><span class="special">,</span> <span class="identifier">Traits</span> <span class="special">&gt;</span> <span class="special">&amp;</span> is<span class="special">,</span> 
             <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> ed<span class="special">)</span><span class="special">;</span></pre>
<p>Reads the distribution from a std::istream. </p>
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<pre class="literallayout"><span class="keyword">bool</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1ab81a315939fe0cddc4f3764d0938406f"></a><span class="keyword">operator</span><span class="special">==</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> lhs<span class="special">,</span> 
                <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> rhs<span class="special">)</span><span class="special">;</span></pre>
<p>Returns true iff the two distributions will produce identical sequences of values given equal generators. </p>
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<pre class="literallayout"><span class="keyword">bool</span> <a name="doxygen.headers.classboost_1_1random_1_1exponential__distribution_1a442190cef7645076788fef24b574b494"></a><span class="keyword">operator</span><span class="special">!=</span><span class="special">(</span><span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> lhs<span class="special">,</span> 
                <span class="keyword">const</span> <a class="link" href="classboost_1_1random_1_1exponential__distribution.html" title="Class template exponential_distribution">exponential_distribution</a> <span class="special">&amp;</span> rhs<span class="special">)</span><span class="special">;</span></pre>
<p>Returns true iff the two distributions will produce different sequences of values given equal generators. </p>
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